/*
package NiuKe;

import java.util.Scanner;

*/
/**
 * @Description:
 * @Author: Hanzao
 * @Date: 2022/06/21/0:57
 *//*

public class HJ91 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int hang = scanner.nextInt()+1;
        int lie = scanner.nextInt()+1;
        int[][] arr = new int[hang][lie];
        for(int i=0;i<hang;i++){
            arr[i][0] = 1;
        }
        for(int i=0;i<lie;i++){
            arr[0][i] = 1;
        }
//        for(int i=0;i<hang;i++){
//            for(int j=0;j<lie;j++){
//                System.out.print(arr[i][j]+" ");
//            }
//            System.out.println("");
//        }
        for(int i=1;i<hang;i++){
            for(int j=1;j<lie;j++){
                arr[i][j] = arr[i][j-1]+arr[i-1][j];
            }
        }
        System.out.println(arr[hang-1][lie-1]);
    }
}
*/
